A cool HTML editor applet
Enter, Kafenio.editor: a platform independent, open-source HTML-WYSIWYG-Editor. (note: it's still in beta)
There's both screenshots and a demo on the web site. It looks really good.
I did find a couple small issues using it on my Mac. e.g. the common issue of using CTRL-B for selecting bold rather than COMMAND-B. It's just beta software so we can expect a couple rough edges.
Looks to be a good start.